Do I need to treat thyroid too, or is it enough to treat the adrenal fatigue?

I am confused about the difference between symptoms of adrenal fatigue and the symptoms of hypothyroid, and the relationship between them. If I have been treated for adrenal fatigue, and most of my symptoms are cleared up, do I still need to worry about hypothyroid?

I will list my thyroid test results over the years first, then a brief summary of symptoms/treatment.

2/09 (age 34): Depression and anxiety much worse; so enveloping that I couldn't see them until after seeing some improvement with progesterone cream, prescribed in 2/09. Went to doctor when frequent depression convinced me I had to do something. Continuing symptoms; low blood pressure at times, especially in summer/heat; low blood sugar at times, especially with caffeine; insomnia, especially before period; lactose-intolerance a new issue. After 6 weeks on progesterone cream (20mg/day), began seeing tremendous improvement; anxiety and anger returned if I ran out. Using Jarrow-brand PS-100 to help with insomnia.

At this point doctor started lowering hydrocortisone dose: from 5mg to 3mg, then in 6 months 3 mg to 2 mg, then in 6 months 2 mg to 1 mg. Every time dosage is lowered, anxiety symptoms return to varying degrees for a couple of months before things level out again; have had to use anti-anxiety med, then wean off. Currently using essential oils for cleansing and adrenal support, and have not needed anti-anxiety med.

Current: Continuing symptoms are migraine headaches, which no longer respond to excedrin (I take imitrex/alleve/sudafed for them) (triggered by sinus congestion, eyestrain, end/beginning of menstrual cycle, and/or stress); occasional heart palpitations (last about a minute, then go away); increasingly short menstrual cycles (last one 21 days) of irregular length (anywhere from 22 to 29 over the last year, average 24/25 days); periods that completely stop for about 24 hrs on the 3rd or 4th day, then start up again; some problems with orthostatic low blood pressure, esp when hot out, but not as much as before treatment for adrenal fatigue.

A friend and I were discussing hypothyroid, and she thought that a TSH level chronically above 2.0 could signal a problem. Other than the cyclical migraines & short menstrual cycles, I'm not sure I really have any hypothyroid symptoms; it's difficult to tell what the crossover is between adrenal & thyroid issues. And despite weight gain being a symptom of both adrenal issues and hypothyroid, I have never had any problems with that; sometimes I struggle with keeping weight on. (I am 5'5" and weigh 113 lbs.)

Should I leave well-enough alone? Pursue more thyroid testing? If so, what should be tested, and how? Thanks.